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1.
Nat Biomed Eng ; 2020 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-32231314

RESUMO

Strategies for selectively imaging and delivering drugs to tumours typically leverage differentially upregulated surface molecules on cancer cells. Here, we show that intravenously injected carbon quantum dots, functionalized with multiple paired α-carboxyl and amino groups that bind to the large neutral amino acid transporter 1 (which is expressed in most tumours), selectively accumulate in human tumour xenografts in mice and in an orthotopic mouse model of human glioma. The functionalized quantum dots, which structurally mimic large amino acids and can be loaded with aromatic drugs through π-π stacking interactions, enabled-in the absence of detectable toxicity-near-infrared fluorescence and photoacoustic imaging of the tumours and a reduction in tumour burden after the targeted delivery of chemotherapeutics to the tumours. The versatility of functionalization and high tumour selectivity of the quantum dots make them broadly suitable for tumour-specific imaging and drug delivery.

2.
PLoS One ; 15(3): e0229648, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32119707

RESUMO

BACKGROUND: Hemopericardium is a common and hazardous complication of acute type A aortic dissection (ATAAD). This retrospective study aimed to clarify the short-term and mid-term outcomes in patients who underwent surgical rescues for hemopericardium complicated by ATAAD. METHODS: Between January 2007 and March 2019, 586 consecutive patients underwent ATAAD repair at our institution. According to preoperative computed tomography, hemopericardium was found in 191 patients (32.6%), 150 were stabilized with medical treatment, and 41 underwent surgical rescues for critical hemodynamics. The 41 patients were classified into groups according to their rescue procedures: emergent subxiphoid pericardiotomy (E-SXP group, n = 26, 63.4%) or emergent cardiopulmonary bypass (E-CPB group, n = 15, 36.6%). Clinical features, surgical information, postoperative complications, and 3-year survival were analyzed and compared. RESULTS: Demographics, comorbidities and aortic repair procedures were generally homogenous between the two groups, except for sex. The average systolic blood pressure was 62.4 ± 13.3 mmHg and 67.1 ± 13.1 mmHg in the E-SXP and E-CPB groups, respectively. A total of 29.3% of patients underwent cardiopulmonary resuscitation (CPR) before surgical rescues. The in-hospital mortality was similar (30.8% versus 33.3%, P = 0.865) in the two groups. Multivariate analysis revealed that preoperative CPR was an in-hospital predictor of mortality. For patients who survived to discharge, 3-year cumulative survival rates were 87.8% ± 8.1% and 60.0% ± 19.7% in the E-SXP and E-CPB groups, respectively (P = 0.170). CONCLUSIONS: Patients who underwent surgical rescues for ATAAD-complicated hemopericardium are at a high risk of in-hospital mortality. The two rescue procedures revealed similar short-term and mid-term outcomes.

3.
Artigo em Inglês | MEDLINE | ID: mdl-32011799

RESUMO

Herein, the trackable supramolecular transformation of a two-component molecular cage to a three-component cage through supramolecular fusion with another two-component molecular square is described. The use of tetraphenylethene (TPE), a chromophore with aggregation-induced emission (AIE) character, as a component for the molecular cages enables facile fluorescence monitoring of the transformation process: while both cages exhibit fluorescence emission via the restriction of intramolecular motion of the TPE motif, the interactions between TPE and 4,4'-bipyridine introduced in the supramolecular fusion process result in partial fluorescence quenching and shifts in the emission maximum. This study provides a simple and efficient approach towards complex supramolecular cages with emergent functions and demonstrates that AIE features could provide unique opportunities for the characterization of complex, dynamic supramolecular transformation processes.

4.
J Mass Spectrom ; 55(1): e4463, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31671229

RESUMO

Noncovalent interactions between drugs and proteins play significant roles for drug metabolisms and drug discoveries. Mass spectrometry has been a commonly used method for studying noncovalent interactions. However, the harsh ionization process in electrospray ionization mass spectrometry (ESI-MS) is not conducive to the preservation of noncovalent and unstable biomolecular complexes compared with the cold spray ionization mass spectrometry (CSI-MS). A cold spray ionization providing a stable solvation-ionization at low temperature is milder than ESI, which was more suitable for studying noncovalent drug-protein complexes with exact stoichiometries. In this paper, we apply CSI-MS to explore the interactions of ginsenosides toward amyloid-ß-peptide (Aß) and clarify the therapeutic effect of ginsenosides on Alzheimer's disease (AD) at the molecular level for the first time. The interactions of ginsenosides with Aß were performed by CSI-MS and ESI-MS, respectively. The ginsenosides Rg1 bounded to Aß at the stoichiometries of 1:1 to 5:1 could be characterized by CSI-MS, while dehydration products are more readily available by ESI-MS. The binding force depends on the number of glycosyls and the type of ginsenosides. The relative binding affinities were sorted in order as follows: Rg1 ≈ Re > Rd ≈ Rg2 > Rh2, protopanaxatriol by competition experiments, which were supported by molecular docking experiment. CSI-MS is expected to be a more appropriate approach to determine the weak but specific interactions of proteins with other natural products especially polyhydroxy compounds.


Assuntos
Peptídeos beta-Amiloides/química , Ginsenosídeos/química , Simulação de Acoplamento Molecular/métodos , Espectrometria de Massas por Ionização por Electrospray/métodos , Sítios de Ligação , Ligação Proteica , Sapogeninas/química , Relação Estrutura-Atividade
5.
Am J Surg Pathol ; 44(2): 232-240, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31688139

RESUMO

Pleomorphic mantle cell lymphoma (PMCL) can closely mimic diffuse large B-cell lymphoma (DLBCL) morphologically, and expression of CD5 and cyclin D1 is helpful for differential diagnosis. To date, no cases of CD5/cyclin D1 double-negative PMCL have been reported. Four cases of B-cell lymphoma with an immunophenotype of CD5(-) cyclin D1(-) SOX11(+) and morphologic features compatible with DLBCL were included. Two were previously identified, and the other 2 were screened from 500 cases of B-cell lymphoma. We analyzed their clinicopathologic, immunophenotypic, genetic, and gene expression features. Cases of cyclin D1-positive PMCL, cyclin D1-negative PMCL, germinal center B-cell (GCB) DLBCL, and activated B cell (ABC) DLBCL were also studied for comparison. Similar to other PMCL cases, these 4 patients were mainly elderly male individuals with an aggressive clinical course. None of these tumors had detectable translocations involving CCND1, CCND2, CCND3, CCNE1, CCNE2, MYC, BCL2, or BCL6. The genome-wide copy number profile of these 4 cases was similar to that of cyclin D1-negative PMCL. None of these tumors had high expression of cyclin D1, cyclin D2, or cyclin D3. Similar to cyclin D1-negative PMCL, these cases had higher expression of cyclin E1 and cyclin E2 compared with cyclin D1-positive PMCL. The gene expression pattern of these tumors was also similar to that of cyclin D1-negative PMCL. Here we report for the first time 4 cases of CD5/cyclin D1 double-negative PMCL. SOX11 positivity is useful to identify these rare tumors, and further genetic and gene expression analysis can be used to confirm the diagnosis.

6.
World J Gastroenterol ; 25(47): 6813-6822, 2019 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-31885422

RESUMO

BACKGROUND: Ulcerative colitis (UC) is a chronic, nonspecific intestinal inflammatory disease with undefined pathogenesis. Non-SMC condensin I complex subunit D2 (NCAPD2) and non-SMC condensin II complex subunit D3 (NCAPD3) play pivotal roles in chromosome assembly and segregation during both mitosis and meiosis. To date, there has been no relevant report about the functional role of NCAPD2 and NCAPD3 in UC. AIM: To determine the level of NCAPD2/3 in intestinal mucosa and explore the mechanisms of NCAPD2/3 in UC. METHODS: Levels of NCAPD2/3 in intestinal tissue were detected in 30 UC patients and 30 healthy individuals with in situ hybridization (ISH). In vitro, NCM60 cells were divided into the NC group, model group, si-NCAPD2 group, si-NCAPD3 group and si-NCAPD2+si-NCAPD3 group. Inflammatory cytokines were measured by ELISA, IKK and NF-κB were evaluated by western blot, and IKK nucleation and NF-κB volume were analyzed by immunofluorescence assay. RESULTS: Compared with expression in healthy individuals, NCAPD2 and NCAPD3 expression in intestinal tissue was significantly upregulated (P < 0.001) in UC patients. Compared with levels in the model group, IL-1ß, IL-6 and TNF-α in the si-NCAPD2, si-NCAPD3 and si-NCAPD2+si-NCAPD3 groups were significantly downregulated (P < 0.01). IKK and NF-κB protein expression in the si-NCAPD2, si-NCAPD3 and si-NCAPD2+si-NCAPD3 groups was significantly decreased (P < 0.01). Moreover, IKK nucleation and NF-κB volume were suppressed upon si-NCAPD2, si-NCAPD3 and si-NCAPD2+ si-NCAPD3 transfection. CONCLUSION: NCAPD2/3 is highly expressed in the intestinal mucosa of patients with active UC. Overexpression of NCAPD2/3 promotes the release of pro-inflammatory cytokines by modulating the IKK/NF-κB signaling pathway.

7.
Nanoscale ; 11(46): 22222-22229, 2019 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-31735945

RESUMO

Microwave-induced thermoacoustic imaging (MTAI) utilizes the high dielectric contrast of tissues in the microwave range, and, combined with the high resolution of ultrasound imaging, can noninvasively obtain anatomical and functional structure information. However, adequate contrast in certain indications (e.g., breast tumor in their early stages) can be difficult to achieve due to the minimal dielectric difference in the target tissues. A tumor specific targeting nanoparticle with high dielectric loss would enhance MTAI contrast in such applications. In this work, we propose a physics-principle-based technique that increases the dielectric loss of a nanoparticle by increasing its atomic defect to generate an amplified thermoacoustic signal. In principle, bovine serum albumin loaded on graphene oxide (GO) serves as a reductant to create additional vacancies in GO to produce more electric dipoles. Upon pulsed microwave irradiation, the defect dipoles are polarized repeatedly, causing transient heating and thermoelastic expansion, and ultimately generating an amplified acoustic wave. This hypothesis was tested in vitro and in vivo with a breast tumor animal model. The results demonstrate that the nanoparticle can effectively enhance the MTAI contrast of breast tumors. The physics-principle-based technique is likely to contribute to early breast tumor imaging.

8.
Nanomaterials (Basel) ; 9(12)2019 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-31766325

RESUMO

In this study, TiO2-NiO heterostructures were synthesized by combining hydrothermal and chemical bath deposition methods. The post-annealing temperature was varied to control the surface features of the TiO2-NiO heterostructures. TiO2-NiO heterostructures annealed at 350 °C comprised NiO-nanosheet-decorated TiO2 nanostructures (NST), whereas those annealed at 500 °C comprised NiO-nanoparticle-decorated TiO2 nanostructures (NPT). The NPT exhibited higher photodegradation activity than the NST in terms of methylene blue (MB) degradation under irradiation. Structural analyses demonstrated that the NPT had a higher surface adsorption capability for MB dyes and superior light-harvesting ability; thus, they exhibited greater photodegradation ability toward MB dyes. In addition, the NST showed high gas-sensing responses compared with the NPT when exposed to acetone vapor. This result was attributable to the higher number of oxygen-deficient regions on the surfaces of the NST, which increased the amount of surface-chemisorbed oxygen species. This resulted in a relatively large resistance variation for the NST when exposed to acetone vapor.

9.
PLoS One ; 14(11): e0214976, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31756182

RESUMO

In this study, two anoxic-oxic membrane bioreactor (A/O-MBR) systems, i.e. conventional and biofilm anoxic-oxic-membrane bioreactors (C-A/O-MBR and BF-A/O-MBR, respectively), were operated in parallel under conditions of complete sludge retention for the purposes of comparing system performance and microbial community composition. Moreover, with the microbial communities, comparisons were made between the adhesive stage and the suspended stage. High average removal of COD, NH4+-N and TN was achieved in both systems. However, TP removal efficiency was remarkably higher in BF-A/O-MBR when compared with C-A/O-MBR. TP mass balance analysis suggested that under complete sludge retention, polyurethane sponges that were added into the anoxic tank played a key role in both phosphorus release and accumulation. The qPCR analysis showed that sponge biomass could maintain a higher level of abundance of total bacteria than the suspended sludge. Meanwhile, AOB and denitrifiers were enriched in the suspended sludge but not in the sponge biomass. Results of illumina sequencing reveal that the compacted sponge in BF-A/O-MBR could promote the growth of bacteria involved in nutrient removal and reduce the amount of filamentous and bacterial growth that is related to membrane fouling in the suspended sludge.

10.
Nanotechnology ; 30(49): 495701, 2019 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-31539365

RESUMO

In this study, a combinational strategy for synthesizing ZnO nanorod arrays interlaced with Ag2O particles was proposed. Hydrothermally derived ZnO nanorod templates were sputter coated with Ag2O particles. The sputtered Ag2O particles can be decorated on the surfaces of the ZnO nanorod arrays with a randomly dispersive or continuous coverage characteristic by controlling the sputtering duration. Structural analysis revealed the formation of satisfactory crystalline ZnO-Ag2O composite nanorods through the hydrothermal and sputtering methods. The ZnO-Ag2O composite nanorods exhibited a significantly enhanced photoactivity compared with that of pristine ZnO nanorods under light irradiation. Moreover, the Ag2O content and the coverage feature of the ZnO-Ag2O composite nanorods influence the photodegradation of methyl orange solution by the composite nanorods under light irradiation. The photodegradation efficiency of the ZnO nanorods was substantially enhanced when the Ag2O particles were decorated on the surfaces in a dispersive manner. This can be attributed to the optimal content of Ag2O particles and their randomly dispersive characteristic on the surface of the composite nanorods, which resulted in the efficient transfer of photocarriers and markedly suppressed the electron-hole recombination rate.

11.
Blood Adv ; 3(15): 2355-2367, 2019 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-31395598

RESUMO

Plant homeodomain finger gene 6 (PHF6) encodes a 365-amino-acid protein containing 2 plant homology domain fingers. Germline mutations of human PHF6 cause Börjeson-Forssman-Lehmann syndrome, a congenital neurodevelopmental disorder. Loss-of-function mutations of PHF6 are detected in patients with acute leukemia, mainly of T-cell lineage and in a small proportion of myeloid lineage. The functions of PHF6 in physiological hematopoiesis and leukemogenesis remain incompletely defined. To address this question, we generated a conditional Phf6 knockout mouse model and investigated the impact of Phf6 loss on the hematopoietic system. We found that Phf6 knockout mice at 8 weeks of age had reduced numbers of CD4+ and CD8+ T cells in the peripheral blood compared with the wild-type littermates. There were decreased granulocyte-monocytic progenitors but increased Lin-c-Kit+Sca-1+ cells in the marrow of young Phf6 knockout mice. Functional studies, including competitive repopulation unit and serial transplantation assays, revealed an enhanced reconstitution and self-renewal capacity in Phf6 knockout hematopoietic stem cells (HSCs). Aged Phf6 knockout mice had myelodysplasia-like presentations, including decreased platelet counts, megakaryocyte dysplasia, and enlarged spleen related to extramedullary hematopoiesis. Moreover, we found that Phf6 loss lowered the threshold of NOTCH1-induced leukemic transformation at least partially through increased leukemia-initiating cells. Transcriptome analysis on the restrictive rare HSC subpopulations revealed upregulated cell cycling and oncogenic functions, with alteration of key gene expression in those pathways. In summary, our studies show the in vivo crucial roles of Phf6 in physiological and malignant hematopoiesis.

12.
Nanomaterials (Basel) ; 9(8)2019 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-31405208

RESUMO

TiO2-Ag2O composite nanorods with various Ag2O configurations were synthesized by a two-step process, in which the core TiO2 nanorods were prepared by the hydrothermal method and subsequently the Ag2O crystals were deposited by sputtering deposition. Two types of the TiO2-Ag2O composite nanorods were fabricated; specifically, discrete Ag2O particle-decorated TiO2 composite nanorods and layered Ag2O-encapsulated TiO2 core-shell nanorods were designed by controlling the sputtering duration of the Ag2O. The structural analysis revealed that the TiO2-Ag2O composite nanorods have high crystallinity. Moreover, precise control of the Ag2O sputtering duration realized the dispersive decoration of the Ag2O particles on the surfaces of the TiO2 nanorods. By contrast, aggregation of the massive Ag2O particles occurred with a prolonged Ag2O sputtering duration; this engendered a layered coverage of the Ag2O clusters on the surfaces of the TiO2 nanorods. The TiO2-Ag2O composite nanorods with different Ag2O coverage morphologies were used as chemoresistive sensors for the detection of trace amounts of NO2 gas. The NO2 gas-sensing performances of various TiO2-Ag2O composite nanorods were compared with that of pristine TiO2 nanorods. The underlying mechanisms for the enhanced sensing performance were also discussed.

13.
Int J Nurs Sci ; 6(1): 24-30, 2019 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-31406865

RESUMO

Objectives: Maker education is a dominant force in education reform and is viewed as a revolutionary way to learn. As innovative pedagogy is continuously explored in the field of nursing, the emerging role of maker education must be examined. This research aims to build a nursing bachelor education program based on maker education and to evaluate the effectiveness of this program. Methods: Forty volunteer junior students majoring in nursing from a college were the subjects for this quasi-experiment. The training program for nursing students based on maker education was developed and implemented as an additional class for a period of 12 weeks. Before and after the experiment, two measures including the "Williams Creative Scale" and "Current Status Questionnaire of Nursing Students' Learning" were adopted for investigation, and corresponding statistical methods were used for analysis. The degree of satisfaction with this training program was investigated after the experiment. Results: The average scores of creativity, learning interest, cooperative learning skill, scientific research ability, and information attainment of the nursing students after the implementation of maker education all improved. The differences in the above points before and after the experiment were all statistically significant (P < 0.05). Most of the students expressed satisfaction with this training program (72.5% were very satisfied, 15.0% were partially satisfied, and 12.5% were not satisfied). Conclusion: Implementing the training program based on maker education enhanced student creativity, learning interest, cooperative learning skill, scientific research ability, and information attainment. Comprehensive nursing talents were also cultivated. Our data suggested the importance of improving this program, adopting the method, and pursuing research in nursing education.

14.
Environ Pollut ; 254(Pt A): 112848, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31421578

RESUMO

This study demonstrates the use of positive matrix factorization (PMF) in a region with a major Petrochemical Complex, a prominent source of volatile organic compounds (VOCs), as a showcase of PMF applications. The PMF analysis fully exploited the quality and quantity of the observation data, sufficed by a cluster of 9 monitoring sites within a 20 km radius of the petro-complex. Each site provided continuous data of 54 speciated VOCs and meteorological variables. Wind characteristics were highly seasonal and played a decisive role in the source-receptor relationship, hence the dataset was divided into three sub-sets in accordance with the prevailing wind flows. A full year of real-time data were analyzed by PMF to resolve into various distinct source types including petrochemical, urban, evaporative, long-range air parcels, etc., with some sites receiving more petro-influence than others. To minimize subjectivity in the assignment of the PMF source factors, as commonly seen in some PMF works, this study attempted to solidify PMF results by supporting with two tools of spatially/temporally resolved air-quality model simulations and observation data. By exploiting the two supporting tools, the dynamic process of individual sources to a receptor were rationalized. Percent contributions from these sources to the receptor sites were calculated by summing over the occurrence of different source types. Interestingly, although the Petro-complex is the single largest local VOC source in the 20 km radius study domain, all monitoring sites in the region received far less influence from the Petro-complex than from other emission types within or outside the region, which together add up to more than 70% of the total VOC abundance.


Assuntos
Poluentes Atmosféricos/análise , Poluição do Ar/estatística & dados numéricos , Monitoramento Ambiental/métodos , Compostos Orgânicos Voláteis/análise , Poluição do Ar/análise , Modelos Químicos , Vento
15.
Front Neurol ; 10: 882, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31456742

RESUMO

Background and purpose: Hypoperfusion plays an important role in the pathophysiology of cerebral small vessel disease (SVD). Lenticulostriate arteries (LSAs) are some of the most important cerebral arterial small vessels. This study aimed to investigate whether the number of LSAs was associated with the cerebral perfusion in SVD patients and determine the correlation between the number of LSAs and SVD severity. Methods: Five hundred and ninety-four consecutive patients who underwent digital subtraction angiography were enrolled in this study. The number of LSAs was determined. Computed tomography perfusion (CTP) was used to calculate the cerebral blood flow (CBF), cerebral blood volume (CBV), mean transit time (MTT), and time to peak (TTP). Magnetic resonance imaging (MRI) was performed to assess cerebral infarct, cerebral microbleeds (CMBs), white matter hyperintensities (WMHs), enlarged perivascular spaces (EPVSs), and lacunes. An SVD compound score was calculated to express the level of cerebral SVD load. Results: The SVD scores were negatively correlated with the number of the LSAs (P < 0.001, r s = -0.44). The number of LSAs was inversely associated with the presence of any type of SVD (P < 0.001). The adjusted ORs of the SVD severity were 0.31 for LSA group 1 (LSA > 20) vs. group 2 (LSA = 10-20) and 0.47 for LSA group 2 (LSA = 10-20) vs. group 3 (LSA < 10). MTT and TTP were significantly higher and CBF was significantly lower when the number of LSAs was between 5 and 10 on each side of the basal ganglia (P < 0.001, <0.001, and <0.001, respectively). The CBV was slightly lower when the number of LSAs was between 5 and 10, while it was significantly lower when the number was <5 on each side of the basal ganglia (P < 0.05, <0.0001, respectively). Conclusion: LSA count was lower in SVD patients than the non-SVD participants and there was a positive correlation between the cerebral perfusion and the number of LSAs. The LSA number was negatively associated with SVD severity, hypoperfusion might play an important role. This finding may have potentially important clinical implications for monitoring LSA in SVD patients.

16.
J Med Chem ; 62(14): 6694-6704, 2019 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-31274302

RESUMO

The early noninvasive diagnosis of Alzheimer's disease targeted ß-amyloid (Aß) plaques or Tau tangles is a major challenge because of the coshared ß-sheet structure of the target. In contrast to tailoring probes to specific amyloids, here, we showed that near-infrared (NIR) environment-sensitive probe 18 could fluorescently discriminate Aß and Tau from artificial aggregates to pathological change in the brain tissue. The biological evaluation demonstrated that the substantial fluorescence enhancement, large blueshift in the emission upon interactions with the aggregates, and the high binding affinity significantly contributed to the fluorescent discrimination. A simplified Ooshika-Lippert-Mataga equation provided an effective means of correlating 18 with the static relative permittivity (ε0) of proteins, elucidating the origin of the distinction capabilities, and quantitatively estimating the dielectric properties of proteins. Moreover, 18 possessed high bioavailability, including sufficient blood-brain barrier penetration, in vivo NIR imaging, and ex vivo histology in living mice.

17.
Nat Hum Behav ; 3(9): 962-973, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31263289

RESUMO

People tend to believe that their perceptions are veridical representations of the world, but also commonly report perceiving what they want to see or hear. It remains unclear whether this reflects an actual change in what people perceive or merely a bias in their responding. Here we manipulated the percept that participants wanted to see as they performed a visual categorization task. Even though the reward-maximizing strategy was to perform the task accurately, the manipulation biased participants' perceptual judgements. Motivation increased neural activity selective for the motivationally relevant category, indicating a bias in participants' neural representation of the presented image. Using a drift diffusion model, we decomposed motivated seeing into response and perceptual components. Response bias was associated with anticipatory activity in the nucleus accumbens, whereas perceptual bias tracked category-selective neural activity. Our results provide a computational description of how the drive for reward leads to inaccurate representations of the world.


Assuntos
Motivação , Percepção Visual , Adolescente , Adulto , Viés , Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Formação de Conceito/fisiologia , Feminino , Neuroimagem Funcional , Humanos , Imagem por Ressonância Magnética , Masculino , Motivação/fisiologia , Núcleo Accumbens/diagnóstico por imagem , Núcleo Accumbens/fisiologia , Estimulação Luminosa , Recompensa , Percepção Visual/fisiologia , Adulto Jovem
18.
Oncol Rep ; 42(3): 1005-1016, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31322264

RESUMO

According to a report of the International Agency for Research on Cancer, arsenic and inorganic arsenic compounds are classified into Group 1 carcinogens with regard to human health. Epidemiological studies indicate that arsenic is one of the main risk factors for the development of bladder cancer. In the present study, arsenic­altered gene expression in mouse bladder tissues and in human urothelial cells was compared. In the mouse model, sodium arsenite­induced mouse urothelial hyperplasia and intracellular inclusions were present. Following DNA array analysis, four genes with differential expression were selected for quantitative real­time PCR assay. The genes were the following: Cystathionine ß­synthase (CBS), adenosine A1 receptor (ADORA1), metastasis­associated lung adenocarcinoma transcript 1 (MALAT1) and Wnt inhibitory factor 1 (Wif1). The results indicated a significant increase in the levels of Cbs and Adora1. The analysis of the DNA CpG methylation levels of the mouse Cbs and Adora1 genes revealed no significant change. In contrast to these observations, the four genes were further analyzed in the human normal urothelial cell line SV­HUC1. The data indicated that WIF1 gene expression was decreased by sodium arsenite, whereas this was not noted for CBS, MALAT1 and ADORA1. Sodium arsenite decreased mRNA and protein expression levels of the WIF1 gene. In addition, the methylation levels of the WIF1 gene were increased. Sodium arsenite inhibited cell proliferation and promoted cell migration as demonstrated in cell functional assays. The gene status was compared in 8 human urothelial cell lines, and WIF1 mRNA expression levels were determined to be higher, whereas DNA CpG methylation levels were lower in SV­HUC1 cells compared with those noted in the other 7 bladder cancer cell lines. In summary, the data indicated that sodium arsenite decreased WIF1 gene expression and promoted cell migration. The increased methylation levels of WIF1 DNA CpG could be a potential biomarker for bladder cancer.


Assuntos
Arsênico/farmacologia , Biomarcadores Tumorais/metabolismo , Metilação de DNA/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Neoplasias da Bexiga Urinária/patologia , Bexiga Urinária/patologia , Urotélio/patologia , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Apoptose , Biomarcadores Tumorais/genética , Movimento Celular , Proliferação de Células , Feminino , Perfilação da Expressão Gênica , Humanos , Metionina Sulfóxido Redutases/genética , Metionina Sulfóxido Redutases/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Proteínas dos Microfilamentos/genética , Proteínas dos Microfilamentos/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Receptor A2A de Adenosina/genética , Receptor A2A de Adenosina/metabolismo , Células Tumorais Cultivadas , Bexiga Urinária/efeitos dos fármacos , Bexiga Urinária/metabolismo , Neoplasias da Bexiga Urinária/tratamento farmacológico , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/metabolismo , Urotélio/efeitos dos fármacos , Urotélio/metabolismo
19.
Biochem Biophys Res Commun ; 515(2): 289-295, 2019 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-31146920

RESUMO

Successful seed germination depends on the rapid repair of cell membrane damaged by dry storage. However, little is known about the reorganization of lipids during this process. In this study, the changes of intracellular redox environment, cell membrane integrity, lipid composition, and expression of genes related to phospholipid metabolism were assessed during imbibition of Brassica napus seeds. A total number of 443 lipids belonging to 7 categories were detected by ultra-performance liquid chromatography/quadrupole time-of-flight mass spectrometry (UPLC-QTOF-MS/MS). In the 24 h-imbibed seeds, the relative content of triacylglycerol was lower than in dry seeds, while the relative content of phosphatidylcholine (PC), phosphatidylethanolamine (PE), phosphatidylinositol (PI), and phosphatidylserine (PS), especially PC (36:2, number of carbons in the acyl chains: number of double bonds), PC (36:3), and PE (36:3) were higher than those in dry seeds. Meanwhile, the content and unsaturation levels of phospholipids increased, indicating membrane lipids remodeling during seed imbibition. The plasma membrane integrity, which was measured by the relative electrolyte leakage (REL) of the membrane and FM4-64 fluorescent dye, was improved upon imbibition, confirming that cell membrane was repaired after 24 h-imbibition. The reduction of H2O2 content, redox potential, and malondialdehyde (MDA) content indicated that the degree of membrane lipid peroxidation was significantly decreased upon imbibition. Gene expression analysis showed that the differential expression of genes for key enzymes occurred in the plateau phase of the imbibition curve, i.e. after 8 h-to 24 h-imbibition. Moreover, the differential expression of genes such as those encoding phospholipase C (PLC), phospholipase D (PLD), triacylglycerol lipase (TAG lipase), choline/ethanolamine phosphotransferase (CEPT), and phosphatidylserine synthase (PTDSS2) during imbibition indicated that membrane lipid remodeling was related to complex metabolic pathways, among which the degradation of triacylglycerol and the synthesis of phospholipids using diacylglycerol might play an important role during membrane remodeling.

20.
Nanomaterials (Basel) ; 9(6)2019 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-31174373

RESUMO

WO3-SnO2 composite nanorods were synthesized by combining hydrothermal growth of tapered tungsten trioxide (WO3) nanorods and sputter deposition of thin SnO2 layers. Crystalline SnO2 coverage layers with thicknesses in the range of 13-34 nm were sputter coated onto WO3 nanorods by controlling the sputtering duration of the SnO2. The X-ray diffraction (XRD) analysis results demonstrated that crystalline hexagonal WO3-tetragonal SnO2 composite nanorods were formed. The microstructural analysis revealed that the SnO2 coverage layers were in a polycrystalline feature. The elemental distribution analysis revealed that the SnO2 thin layers homogeneously covered the surfaces of the hexagonally structured WO3 nanorods. The WO3-SnO2 composite nanorods with the thinnest SnO2 coverage layer showed superior gas-sensing response to 100-1000 ppm acetone vapor compared to other composite nanorods investigated in this study. The substantially improved gas-sensing responses to acetone vapor of the hexagonally structured WO3 nanorods coated with the SnO2 coverage layers are discussed in relation to the thickness of SnO2 coverage layers and the core-shell configuration of the WO3-SnO2 composite nanorods.

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